Brake for spinning and twisting spindles

ABSTRACT

The clamping show is resiliently connected to the housing to move radially on the spindle upon braking of the elastically supported spindle by means of the brake elements on the shoe. The resilient connection can be formed by reduced portions in the arms of the shoe or by a spring member or one or more springs between the shoe and the housing.

United States Patent [191 Mandl ,luly 16, 1974 [5 BRAKE FOR SPINNING ANDTWISTING 2,638,733 5/1953 Haythornthwaite et al. 57/88 X L 2,975,5843/1961 Makant et al 57/88 3,128,591 4/1964 Hammond 57/88 [75] Inventor:Gerhard Mandl, Wmterthur,

Switzerland Primary Examiner-John Petrakes [73] Assignee: Rieter MachineWorks, Ltd., Attorne A em, or Firm-Ken on & Ken on Reill y 8 Y y YWmterthur, Switzerland Carr & Chapin [22] Filed: Sept. 13, 1972 21 Appl.No.: 288,481 [57] ABSTRACT The clamping show is resiliently connected tothe [52 US. Cl. 57/88 heheihg meve radially eh the Spindle braking 51Int. Cl D01h 7/22 of the eleeheehy ShPPeYted sPihdle by means ef the[58] Field of Search 57/88 89 hrehe elements eh the Shoe The resilienteehheehe" can be formed byreduced portions in the arms of the [56]References Cited shoe or by a spring member or one or more springsUNITED STATES PATENTS between the shoe and the housing.

2,115,268 4/1938 Klein 57/58 6 Claims, 8 Drawing Figures wimtnmuswn V3.823.549

SHEET 1 [IF 2 BRAKE FOR SPINNING AND TWISTING SPINDLES This inventionrelates to a brake for spinning and twisting spindles. Moreparticularly, this invention relates to a brake for a spinning andtwisting spindle supported elastically in radial direction, such as usedon staple fiber spinning and twisting machines or on drawtwistingmachines for processing endless filaments.

Various braking arrangements have been known in which an open supportmember has been positioned in surrounding relation to a brake drum of aspindle with brake elements supported thereon in opposition to the brakedrum. Generally, the support member has been rigidly connected to aspindle bearing housing on a side opposite the open end. In addition,the open ends of the support member have been provided with lappetsinclined with respect to the spindle axis and directed downwardly andoutwardly, while a yoke has been mounted in the lappets. In order tobrake the spindle, the yoke has been moved axially to bring the lappetstogether while closing the support member on the spindle in brakingrelation.

In such a braking arrangement, the support member has been held rigidlyin place on one side by the rigid connection with the bearing housingand on the other side by the rigidly guided yoke. Thus, the geometricaxis of the support member always remains in the same fixed position.Other braking arrangements have also been known in which a supportmember has been activated by a pin provided with cams acting betweenradial lappets which extend from the open ends of the support member toeffect opening or closing of the support member. However, in these casesalso, the geometric axes of the brake support members always remainfixed in the same position with respect to thespindle bearing housing.

While these above braking arrangements do not present disadvantages forrigidly supported spindles they do present a problem for spindles whichoperate at high rotation speeds and are flexibly or resilientlysupported. As a result, these resiliently mounted spindles do not rotateabout their geometric axes since they are subject to high-frequencyrelative movements in addition to their pure rotational movement. Theuse of brakes of the aforementioned type, i.e. brakes with a rigidgeometric axis on elastically or resiliently supported spindles, shows amarked disadvantage in that great forces are generated during thebraking action as the axes of the brake and of the spindle do notcoincide during operation. Thus, damage to tubes, spindle blades, whorlsand/or to brake elements can be caused.

Braking devices have also been known in which a braking element or abrake shoe, supported by a flexible element connected via a lever systemacting between the brake element and the connecting point, are pressedagainst the brake drum of a spindle whorl so that a spindle brakingaction is effected. Brakes of this type are provided with an elasticallysupported brake element but show disadvantages in that the brake elementcan yield in only one direction to the spindle movement of anelastically supported spindle. This can permit one-sided pressures toact on the bearing so that the spindle movement would cause additionalunfavorable vibrations which, again, could cause damage as mentionedabove to tubes, spindle blades and whorls.

Braking devices have also been known which are activated by a cablearrangement, a so-called Bowden cable arrangement, wherein the cablepresses a brake element against a brake drum by means of a leverarrangement so that a braking action is effected. The support in whichthe lever arrangement and a cable sash for the cable have beensupported, or fixed respectively, has been rigidly connected to thespindle rail. The cable arrangement, in this case, merely has had thefunction of permitting adjustment of the maximum braing pressure byadjusting the effective cable length. Thus, in spite of a flexible cablearrangement, the disadvantages prevail, namely that the brake elementcannot yield to the radial movement of an elastically supported spindle,which again would cause the damages already mentioned.

Accordingly, it is an object of the invention to permit a brake for aresiliently mounted spindle to yield to the radial movements of thespindle during braking.

It is another object of the invention to maintain the geometric axes ofa resiliently mounted spindle and a surrounding brake in substantialcoincidence during braking.

It is another object of the invention to avoid the generation of largeeccentric forces between a resiliently mounted spindle and a brakeduring braking.

It is another object of the invention to reduce wear between a brake anda resiliently mounted spindle.

Briefly, the invention provides a resiliently mounted spindle with abrake which is also resiliently mounted on a bearing housing for thespindle. The spindle bearing housing is generally secured to a spindlerail and is provided with suitable elements such as springs toelastically or resiliently mount the spindle therein. The spindle, inturn, is provided with a braking surface against which the brake can bepressed. The brake has a clamping shoe on which brake elements aremounted in opposition to the spindle braking surface. This shoe isconstructed to be pressed against the spindle braking surface upontensioning of the shoe. In addition, the shoe is resiliently connectedto the spindle rail to move radially with the spindle braking surfaceupon pressing of the brake elements against the braking surface. Thetensioning of the shoe is carried out by an elastic means connected tothe shoe, for example, by a Bowden cable arrangement.

In one embodiment, the clamping shoe is provided with anns havingreduced portions near the point of securement to the spindle bearinghousing in order to be resilient of itself.

In another embodiment, the clamping shoe is connected by an elastic'orresilient intermediate means to the spindle bearing housing. Thisintermediate means can include one or more springs to effect a resilientconnection or can itself be a spring member.

These and other objects and advantages of the invention will become moreapparent from the following detailed description and appended claimstaken in conjunction with the accompanying drawings in which:

FIG. 1 illustrates a partial cross-sectional view of a radiallyelastically supported spindle with a brake according to the invention;

FIG. 2 illustrates a plan view of the spindle and brake of FIG. 1;

FIG. 3 illustrates a modified resilient connection using a springbetween a clamping shoe and a bearinghousing according to the invention;

FIG. 4 illustrates a further modified resilient connection using a pairof springs between a clamping shoe and a bearing housing according tothe invention;

FIG. illustrates a further modified resilient connection between aclamping shoe and a bearing housing according to the invention;

FIG. 6 illustrates a plan view of the connection of FIG. 3;

FIG. 7 illustrates a plan view of the connection of FIG. 4; and

FIG. 8 illustrates a plan view of the connection of FIG. 5.

Referring to FIG. 1, a spindle rail 1 disposed, for example, on aspinning and twisting frame or a drawtwister, provides a support for anon-rotatable envelope tube 2 into which a spindle 3 is rotatablymounted. The spindle rail 1 has a spindle bearing housing 4 rigidlyconnected thereon by means of a cover flange 5 and screws 6. The spindlebearing housing 4 and cover flange 5 are recessed as shown to secure aplurality of radially disposed springs 7 therebetween which springs 7serve to resiliently connect the envelope tube 2 to the housing 4 and,in turn, to the rail 1. The spindle 3 has a whorl 8 thereon as is knownwhich carries a braking surface or brake drum 9 at the lower end. Abrake is disposed about the braking surface 9 and is formed by aclamping shoe 1] which has a pair of arms surrounding the brakingsurface 9 and a plurality of brake elements 10 (FIG. 2) which aresecured on the shoe in opposition to the braking surface 9. The arms ofthe shoe 11 are biased outwardly of each other relative to the spindle 3so as to normally space the brake elements 10 from the braking surfaceor brake drum 9.

Referring to FIGS. 1 and 2, the clamping shoe 11 is connected by meansof a screw 13 to a mounting angle 14 which, in turn, is fixed to asupport member 15 rigidly secured on the housing 4. The shoe 1] is thusnonrotatably fixed with respect to the housing 4. In addition, the armsof the clamping shoe 11 are each provided with a reduced portion 12 inclose vicinity to the holding screw 13. These reduced portions 12 effecta flexibility or resilient connection of the shoe 11 relative to thespindle rail 1 and housing 4. At the open side of the clamping shoe 11,the ends of the shoe arms are each provided with an arcuate portion 16and with a slot 17 so as to take up a Bowden cable arrangement 18. TheBowden cable arrangement 18 consists of a cable sash 19, a cable 20, aknob 21 held against an arcuate portion 16 of one shoe arm and of a stop22 secured to the spindle rail 1.

In use, if for any reason the spindle 3 is to be braked to a standstill,the Bowden cable arrangement 18 is ac tivated by pulling the cable inthe direction of arrow A (FIG. 1) e.g. by means ofa foot pedal (notshown). The clamping shoe 11 is thus closed on itself so that thebraking elements 10 are pressed against the spindle braking surface 9.As the brake shoe 11 is kept flexible by means of the recesses 12, thebrake elements 10 can follow, or take up the vibrations of the radiallyelastically supported spindle 3. If the spindle 3 is brought to astandstill, the cable 20 can be released again so that the brakeelements 10 are lifted from the braking surface 9 by the inherenttension of the brake shoe 11.

Referring to FIGS. 3 and 6, the clamping shoe 23 which is similar tothat described above can omit the use of reduced arm portions andinstead can be connected by a spiral spring 24 and a screw 25 to themounting angle 14. In this case, the shoe 23 can move relative to thescrew 25 under a biasing force of the spring 23 which presses the shoe23 against the mounting angle 14 during travel with a spindle (notshown). The spring 24 as shown is held between the head of the screw 25and the shoe 23.

Referring to FIGS. 4 and 7, wherein like reference characters indicatelike parts as above, the clamping shoe 23 can be held between twosprings 26, 27 on a screw 25. As shown, one spring 26 is held betweenthe head of the screw 25 and the shoe 23 while the other spring 27 isheld between the mounting angle 14 and the shoe 23.

Referring to FIGS. 5 and 8, wherein like reference characters indicatelike parts as above, the shoe 23 can also be connected directly to thebearing housing 5 my means of an elastic intermediate means such as byone piece spring member 28 as shown.

In use, a clamping shoe with a resilient connection as shown in one ofFIGS. 3 to 8 operates in the same fashion as the shoe 11 described inFIGS. 1 and 2.

The invention thus provides a brake which is of utmost simplicity ofconstruction and thus low manufacturing cost. Also, the inventionpermits the possibility of braking elastically supported spindlesquickly to a standstill from any rotational speed of the speed range,with or without a load being placed on the spindle and without anyadditional vibrations (as described above) being caused and, thus,without damage to the brake or to the rotating elements.

What is claimed is:

1. In combination, a spindle rail, a housing secured to said spindlerail, a spindle having a braking surface thereon and being elasticallysupported radially in said housing, a brake including a clamping shoehaving brake elements for pressing against said braking surface of saidspindle upon tensioning of said shoe and being resiliently connected tosaid spindle rail to move radially with said braking surface uponpressing of said brake elements against said braking surface and elasticmeans connected to said shoe for tensioning of said shoe to press saidbrake elements against said braking surface on said spindle.

2. The combination as set forth in claim 1 wherein said clamping shoeincludes a pair of arms, each said arm having a reduced portion thereinadjacent said housing for effecting a resilient relation between eachsaid arm and said housing.

3. The combination as set forth in claim 1 which further comprises anelastic intermediate means connecting said shoe to said housing.

4. The combination as set forth in claim 3 wherein said elasticintermediate means is a spring member connected between said shoe andsaid housing.

5. The combination as set forth in claim 3 wherein said elasticintermediate means includes at least one spring resiliently biasing saidshoe relative to said housing.

6. The combination as set forth in claim 1 wherein said elastic means isa Bowden cable means.

1. In combination, a spindle rail, a housing secured to said spindlerail, a spindle having a braking surface thereon and being elasticallysupported radially in said housing, a brake including a clamping shoehaving brake elements for pressing against said braking surface of saidspindle upon tensioning of said shoe and being resiliently connected tosaid spindle rail to move radially with said braking surface uponpressing of said brake elements against said braking surface and elasticmeans connected to said shoe for tensioning of said shoe to press saidbrake elements against said braking surface on said spindle.
 2. Thecombination as set forth in claim 1 wherein said clamping shoe includesa pair of arms, each said arm having a reduced portion therein adjacentsaid housing for effecting a resilient relation between each said armand said housing.
 3. The combination as set forth in claim 1 whichfurther comprises an elastic intermediate means connecting said shoe tosaid housing.
 4. The combination as set forth in claim 3 wherein saidelastic intermediate means is a spring member connected between saidshoe and said housing.
 5. The combination as set forth in claim 3wherein said elastic intermediate means includes at least one springresiliently biasing said shoe relative to said housing.
 6. Thecombination as set forth in claim 1 wherein said elastic means is aBowden cable means.